Although it is well established that alcohol can damage any organ or system in the developing foetus - particularly the brain - it remains unknown exactly what makes it most susceptible.

This includes the amount or frequency of alcohol use, or timing of drinking during pregnancy, according to the research published in The Lancet Global Health.

Other factors, such as the genetics, stress, smoking and nutrition also contribute to the risk of developing the disorder, the study says.

The estimates from the study are intended to help countries plan public health initiatives and policies.

These can include monitoring foetal alcohol syndrome, and better education on the risks of alcohol use during pregnancy, the researchers note.

The model that the research team used could also help estimate the prevalence of other disease conditions, Dr Popova added.

Her team is currently extending their work to study the global scale of all foetal alcohol spectrum disorders, FASD.

A previous study by Dr Popova and her team, published in The Lancet last year, showed that more than 400 disease conditions co-occur with FASD.

According to the NHS, “Chief Medical Officers for the UK recommend that if you’re pregnant or planning to become pregnant, the safest approach is not to drink alcohol at all to keep risks to your baby to a minimum.

“Drinking in pregnancy can lead to long-term harm to the baby, with the more you drink, the greater the risk.”